Soft serve machine



FIG. 1 is a perspective view of a soft serve machine showing my new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a left side elevational view; the right side being a mirror image thereof;

FIG. 4 is a top plan view thereof; and

FIG. 5 is a rear elevational view thereof. 

The ornamental design for a soft serve machine, substantially as shown and described. 